DESCRIPTION This application is for the renewal of a training grant first awarded in 1992. The original award was for six predoctoral stipends and two postdoctoral stipends, and the request is to continue at the same level. Dr. Stephen Safe is to continue as the director of this training program, and Dr. Kenneth Ramos is to continue as associate director. In addition, there are seven other faculty who will serve as mentors for both pre and postdoctoral trainees. Students training in toxicology at Texas A & M University enroll in individual departments and train within the faculty of toxicology, one of several interdisciplinary, interdepartmental faculties within the University. The training of predoctoral students and postdoctoral trainees within this training program is carried out within the faculty of toxicology and the separate departments/colleges of the training faculty. The current training faculty derives from the Department of Veterinary Physiology and Pharmacology - Safe and Ramos, the Department of Veterinary Anatomy and Public Health - Phillips, Tiffany-Castiglioni, Busbee, Burghardt, Finnell, and Johnson, and the Department of Biochemistry and Biophysics -Wild. The faculty's research interests are diverse, but complementary. Dr. Burghardt is interested in the role of ligand activated and inositol triphosphate receptor-mediated regulation of gap junction, intercellular communication as a consequence of xenobiotic exposure. Dr. Busbee is using the bottle-nose dolphin as a monitor for environmental contaminant bioaccumulation. Contaminant levels will be correlated with DNA adducts, the capacity to repair DNA damage, and associated response of immune function- related genes. Dr. Finnell studies the influence of environmental toxicants on embryonic development, and its potential teratological consequences. He has also produced mice that lack folate-binding protein genes and will look at the impact of this deficiency on neural tube closure. Dr. Johnson is examining the toxicological effects of dioxins on spermatogenesis and Leydig cell structure and function. Dr. Phillips' research focuses on innovative chemical and biological strategies that allow for detection and subsequent detoxification of hazardous foodborne and environmental toxins. Dr. Ramos studies the role of c-Ha-ras and osteopontin gene expression following xenobiotic exposure, and the consequence of their expression on human diseases such as atherosclerosis, glomerulosclerosis, and renal cancer. Dr. Safe's research deals with the biochemical and toxic effects and the mechanisms of action of TCDD, polynuclear aromatic hydrocarbons and other endocrine disrupters. Dr. Tiffany-Castiglioni focuses her major research effort in the area of lead neurotoxicity, with particular emphasis on the role of astroglia. Dr. Wild's study focuses on the detoxification of organophosphate neurotoxins.